Heat of Reaction MCQs

The heat of reaction refers to the amount of heat released or absorbed when the specified number of moles of reactants, as indicated by the chemical equation, has fully reacted. This quantity, known as the enthalpy change or heat of reaction, is symbolized by ΔH and is typically measured in kilojoules. The heat of reaction can be either negative or positive: ΔH is negative for exothermic reactions, where heat is released, and positive for endothermic reactions, where heat is absorbed. Traditionally, the heat of reaction was determined either directly or indirectly from combustion data, based on the belief that ΔH was the primary driving force behind chemical reactions.

The energy obtained from electric cells and batteries as a result of a chemical reaction is called

(a) chemical energy
(b) nuclear energy
(c) heat energy
(d) electrical energy

In the exothermic reaction, the enthalpy of reaction is always

(a) zero
(b) positive
(c) negative
(d) none of these

As the rain falls the potential energy changes to

(a) thermal energy
(b) chemical energy
(c) kinetic energy
(d) nuclear energy

The amount of heat required to raise the temperature of a body through 1oC is called its

(a) molar heat
(b) specific heat
(c) entropy
(d) thermal capacity

The heat required to raise the temperature of 1 mole of a substance by 1o is called

(a) specific heat
(b) molar heat capacity
(c) water equivalent
(d) specific gravity

The energy released in the form of nuclear radiation in addition to heat and light during nuclear reactions is known as

(a) chemical energy
(b) nuclear energy
(c) heat energy
(d) electrical energy

In the process of rubbing hands, mechanical energy is converted into

(a) sound energy
(b) electrical energy
(c) thermal energy
(d) heat energy

Fireworks release energy in the form of

(a) heat
(b) sound
(c) light
(d) all of the above

When a body vibrates, it produces

(a) sound
(b) water
(c) heat
(d) electricity

The energy coming directly from magma called

(a) mechanical energy
(b) geothermal energy
(c) heat energy
(d) electrical energy